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Fixed one of these new models yesterday.
Looks like fender are in competition with Peavey and ENGL to produce
the world’s hardest amp to service!
The amp had a shorted EL84 but when I replaced them the same socket made the new valve (sorry , Tube) draw excessive current.
Very hard to even see the component side of the PCB but managed to meter the 2 240E 5W cathode resistors, one of which measured 70 Ohms.
I marked all the interconnect leads and removed about 30 screws, lots of cable ties to remove the PCB.
Found the cathode resistors paralleled with 47uF and a 35V 5Watt Zener, one of which had become a resistor.
They probably thought that this very fault condition would not have enough current to damage a 5W clamping zener?
Removed both Zeners, re assembled the mess and all working properly again.
The repair took 4 hours!
The customer came from Albany 30 miles away so I did the repair in front of him.
No schematics are around for this model yet (PR 3034)
Looks like fender are in competition with Peavey and ENGL to produce
the world’s hardest amp to service!
The amp had a shorted EL84 but when I replaced them the same socket made the new valve (sorry , Tube) draw excessive current.
Very hard to even see the component side of the PCB but managed to meter the 2 240E 5W cathode resistors, one of which measured 70 Ohms.
I marked all the interconnect leads and removed about 30 screws, lots of cable ties to remove the PCB.
Found the cathode resistors paralleled with 47uF and a 35V 5Watt Zener, one of which had become a resistor.
They probably thought that this very fault condition would not have enough current to damage a 5W clamping zener?
Removed both Zeners, re assembled the mess and all working properly again.
The repair took 4 hours!
The customer came from Albany 30 miles away so I did the repair in front of him.
No schematics are around for this model yet (PR 3034)
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